Vehicles such as large motor homes and yachts and the like are characterized by a unique set of appliance control problems. Large motor homes and yachts typically are equipped with one or more motor generator sets. When the large motor homes or yachts are stopped at a camp site or moored in a slip, many times a remote source of electrical power is available. When such recreational vehicles are connected to a remote source of electrical power, severe constraints are typically placed on the current that can be drawn from the remote source. As used herein, the term “shore power” will be used to designate such a remote source of electrical power for a recreational vehicle, whether land or sea based. Typically shore power is available as either a 15 amp source, a 20 amp source, a 30 amp source or a 50 amp source.
This current constraint can have dramatic results. For example, if a recreational vehicle is connected to a 20 amp source of electrical power, and the recreational vehicle includes a 15 amp air conditioner, the simultaneous use of a microwave oven or a hair dryer with the air conditioner may well exceed the available current capacity of the remote source, thereby causing circuit breakers to trip or fuses to blow. The replacing of blown fuses or the resetting of tripped circuit breakers can represent a considerable inconvenience to a user of a recreational vehicle in such circumstances.
Another related problem is related to the fact that a variety of recreational vehicles include two air conditioning units or two heating units. When the recreational vehicle is relying on shore power, it may not be feasible to run both air conditioners or both heaters simultaneously because of the power limitations of the shore power connection. For this reason, it has been customary to operate a single one of the two air conditioners from shore power and to leave the other off. This approach can represent a severe inconvenience in a situation where one air conditioner cools a first portion of the recreational vehicle, and the other air conditioner cools a second portion of the recreational vehicle. If only one conditioner is allowed to run, some portion of the recreational vehicle may not be cooled adequately. Furthermore, the approach of manually activating both of the air conditioners or heaters in alternating sequence requires considerable attention by the user.
In addition to being hooked to shore power, either at an RV park or in a slip at a harbor, there are generally two other scenarios where the sources of power must be managed. Dry camping is camping without an electrical hookup or source of power. In this instance, power is provided by on-board batteries and/or on board motor generator set. Power may also be demanded while a coach is underway. For example, a passenger of a yacht or RV may want to use air conditioners or other appliances while enroute from place to place. In this instance, power is generally provided by a motor generator.
Problems relate to determining if the motor generator sets can be used and when to enable the motor generator sets to provide a sufficient level of power for a given load. One condition that must also be avoided is running an air conditioner on less than rated voltage since this can damage the air conditioner. Still another problem is not to use motor generator sets during certain times. Motor generator sets are noisy and many RV parks and slips do not allow operation during night time hours. Thus, the operation of motor generator sets may have other limitations or constraints placed on them that need to be considered.
Still another problem is monitoring all the power systems as the various sources of power and loads are managed. The monitoring must be done so that the operator can tell what is happening in terms of power management. It would be advantageous if a graphical user interface could be used to monitor systems within the recreational vehicle. It would also be advantageous if the monitoring system could reflect very precisely various conditions of various power supplies and devices associated with the recreational vehicle. For example, it would be advantageous if the amount of power available from a DC battery source could be closely monitored.
Yet another problem is that most systems require manual adjustment of several aspects of a power system. For example, when hooking up to “shore power” there are several possible power levels. Currently, the owner operator must manually designate the available power level. In addition, when a converter is used to convert AC to DC power, the maximum charge level of the battery must be manually adjusted.
It would also be advantageous to have certain desired conditions noted and relayed to the owner/operator of the recreational vehicle. For example, if the air conditioning unit in a recreational vehicle is turned off during the day due to a failure of the unit or because too much power is required to run the unit, it would be advantageous to inform the owner/operator if the cabin temperature exceeded a desired threshold level. It would be advantageous if a known link, such as a cellular phone or pager, could be provided with an alert to such conditions. Still another problem is diagnosing problems associated with power sources and appliances and logging these problems. Still another problem is that when a problem does present itself, the priority of the problem is not set forth. Another problem stems from the fact that if a problem is found, there is no way to find a facility to fix a problem or a way to determine how close such a repair facility might be.
Yet another problem is that present power control systems are distributed and not integral. In other words, if there is a problem with motor genset and a heating unit, the repair person must find both the problems separately. In current recreational vehicles, there is not one place where the problems are logged and can be found so the repair person must deal with a variety of interfaces to get logged faults or diagnostic error codes from engines used as the primary mover of the recreational vehicle and other engines used to power a motor generator set and other vehicle and coach systems (CO level detector).
Thus, there are problems with current power systems. What is needed is a an improved power management system that provides an integrated solution and manages the various appliances and which provides a graphical user interface which is user friendly and which repair people can access to get diagnostic codes for various appliances in the recreational vehicle.